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Perl Programming/Keywords/ref

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The ref keyword

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The ref function returns a non-empty string, if EXPRESSION is a reference and an empty string otherwise. Without EXPRESSION, $_ will be used. The returned value depends on the thing referenced to.

ref knows the following types:

Type Notes
ARRAY reference to an array
CODE
FORMAT
GLOB
HASH reference to a hash
IO
LVALUE reference to an lvalue that is not a variable
REF reference to a reference
Regexp regular expression resulting from qr//
SCALAR reference to a scalar
VSTRING

If the referenced object has been blessed into a package, the name of that package is returned instead. This, however, is now considered "bad practice".

Syntax

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  ref EXPRESSION
  ref
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